In conventional NC machine tools and machining centers the tools are normally inserted by hand into the machine's magazines and are manually changed, respectively. When plural machine tools are to be successively loaded with fresh tools, wheel barrows may be used on which the respective tools are placed in an ordered array. This procedure of loading tools into the magazines of plural machine tools is cumbersome and time consuming, because all important operations must be effected manually.
German patent publication No. 3,331,293 discloses a tool changing system for a machine tool with a main tool magazine, in which a tool carriage comprises a track-bound multi-track undercarriage and mounted thereon a plate-like supporting structure. A disk magazine is mounted on said supporting structure for rotation about a horizontal axis, said disk magazine containing a multiplicity of tool cartridges each including plural tools. The column of each machine tool includes a tool changing assembly which has the function of transferring the individual cartridges from the disk magazine of the tool carriage into the machine's own disk magazine.
With this known system there exist difficulties relating to the exact positioning of the individual tool cartridges in the changing position, because the disk magazine of the tool carriage, which forms a tool store, can only be rotated about its central shaft but cannot be accurately positioned as to its height or lateral position. The arrangement of the various tool changing assemblies on the respective machine tools requires relatively high technical effort and additional space.
Further tool loading systems for program controlled machine tools are known, for instance, from Austrian Pat. No. 288,112 and German patent publication No. 3,327,512.